Re: Why so little progress?
It sounds like you desire some strength and whatever CrossFit you go doesn't involve a lot of strength programming.
So you are either going to have to do some on your own or find a CF gym that understands that you want to get stronger and help you with it.
Make sure you're eating enough. See if your form is decent enough.
If SS is too much for you, try another strength building template that isn't as aggressive. 531 comes to mind. In your case, make sure to do the assistance work.
It sounds like you are sick of being weak and slender.